Portland-Limestone Cements: History, Performance, and Specifications
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Portland-Limestone Cements: History, Performance, and Specifications Paul D. Tennis, Ph.D. Portland Cement Association Today’s Objectives What is a portland-limestone blended cement History Environmental performance Concrete performance Changes to the specifications Portland-Limestone Cement Why? Provides an option to implement proven technology to obtain desired performance and improve sustainability of concrete What is Portland-Limestone Cement? ASTM C595 and AASHTO M 240 Blended Cement Type IL or Type IT with limestone 5% to 15% limestone HISTORY History of Limestone in Cements 1965 Cement with 20% limestone in Germany for specialty applications 1979 French cement standards allows limestone additions. 1983 CSA A5 allows up to 5% limestone in portland cement 1990 15±5% limestone blended cements routinely used in Germany 1992 UK specs allows up to 20% in limestone cement 2000 EN 197-1 allows 5% MAC (typ. limestone) in all 27 common cements, History of Limestone in Cements 2000 EN 197-1 creates CEM II/A-L (6-20%) and CEM II/B-L (21-35%) 2004 ASTM C150 allows 5% in Types I-V 2006 CSA A3001 allows 5% in other Types than GU 2007 AASHTO M85 allows 5% in Types I-V 2008 CSA A3001 includes PLC containing 5%-15% limestone European Cement Use 100 1.7 2.1 1.8 2.1 2.2 1.5 1.9 6.1 3.4 2.9 1.8 Others 5 3.2 5.0 5.7 9.5 5.4 CEM V - Composite Cement 90 4.0 6.5 5.5 5.1 5.6 CEM IV - Pozzolanic 5.6 4.8 CEM III - Blast furnace slag 80 14.5 12.5 16.8 9.6 14.3 CEM II - Portland-composite 16.8 CEM II - Portland-limestone 70 CEM II - Portland-fly ash CEM II - Portland-pozzolana 24.0 60 18.9 24.6 15.0 24.5 31.4 CEM II - Portland-slag CEM I - Portland 50 5.4 6.2 7.0 5.7 3.7 2.9 6.9 40 2.1 2.7 4.8 5.4 1.2 7.4 4.2 6.8 5.9 1.4 30 4.5 Cement Types (%) in Europe Types Cement 20 35.4 34.2 33.7 32.1 31.6 27.5 10 0 1999 2000 2001 2002 2003 2004 Cembureau data ENVIRONMENTAL BENEFITS Barcelo, Kline and Walenta, 2012 from Ashby (2009) Energy to Produce Cement Environmental Benefits 10% 15% Energy Reduction* Fuel (million BTU) 443,000 664,000 Electricity (kWh) 6,970,000 10,440,000 Emissions Reduction* SO2 (lb) 581,000 870,000 NOX (lb) 580,000 870,000 CO (lb) 104,000 155,000 CO2 (ton) 189,000 283,000 Total hydrocarbon, THC (lb) 14,300 21,400 * Per million tons cement Environmental Benefits Portland cement 1.0 Portland-limestone cement 0.8 0.6 /kg cement 2 0.4 kg CO 0.2 0.0 Plant 1 Plant 2 Plant 3 Why 15%? How Limestone Works Particle packing Improved particle size distribution Nucleation Surfaces for precipitation Chemical reactions Only a small amount, but… How Limestone Works Particle packing Improved particle size distribution Nucleation Surfaces for precipitation Chemical reactions Only a small amount, but… How Limestone Works Particle packing Improved particle size distribution Nucleation Surfaces for precipitation Chemical reactions Only a small amount, but… ASTM AND AASHTO UPDATES Process JAAHTG reviewed concept January 2010 Technical information from Europe and Canada considered Presented concept to AASHTO TS3a and ASTM C01.10 summer 2010 TS3a ballot in 2011; SOM ballot December 2011. C01.10 ballot April 2011; C01 ballot October 2011 Ballot items passed; 2012 AASHTO M240 and ASTM C595 published AASHTO M240 & ASTM C595 Requirements Type IL—Portland-limestone blended cement Example: Type IL(10) = 10% limestone Type IT—Ternary blended cement with limestone Example 1: Type IT(L12)(P10) = 12% limestone and 10% pozzolan Example 2: Type IT(S15)(L10) = 15% slag and 10% limestone Limestone content 5% to 15% AASHTO M240 & ASTM C595 Requirements Same physical requirement as existing C595/M240 cement types Chemical requirements – sulfate content, LOI Sulfate resistance – no MS or HS in initial specifications Limestone characteristics– CaCO3, MBI, TOC IP IS (<70) IP(LH), IL IL(LH), IS (< 70) (MS), IS (< 70) (HS), IT(P≥S) IT(P≥S)(LH) IT(P<S<70)(MS) IT(P<S<70)(HS) IS(≥70), IT(P>L) IT(L<S<70)(LH) IP(MS), IP (HS), IT(S≥70) IT(L≥S) IT(P>L)(LH) IT(P≥S)(MS) IT(P≥S)(HS) IT(L≥P) IT(L≥S)(LH) IT(L<S<70) IT(L≥P)(LH) IT(P<S<70) Fineness C C C C C Autoclave 0.80 0.80 0.80 0.80 0.80 exp, max, % Autoclave contr, max 0.20 0.20 0.20 0.20 0.20 % Vicat test: minutes, not 45 45 45 45 45 less than hours, not 7 7 7 7 7 more than Air content of mortar, 12 12 12 12 12 volume % IP IS (<70) IP(LH), IL IL(LH), IS (< 70) (MS), IS (< 70) (HS), IT(P≥S) IT(P≥S)(LH) IT(P<S<70)(MS) IT(P<S<70)(HS) IS(≥70), IT(P>L) IT(L<S<70)(LH), IP(MS), IP (HS), IT(S≥70) IT(L≥S) IT(P≥S)(MS) IT(P≥S)(HS) IT(P>L)(LH) IT(L≥P) IT(L≥S)(LH) IT(L<S<70) IT(L≥P)(LH) IT(P<S<70) Compressive strength, min., MPa (psi): 3 days 13.0 11.0 11.0 ... ... (1890) (1600) (1600) ... ... 7 days 20.0 18.0 18.0 5.0 11.0 (2900) (2610) (2610) (720) (1600) 28 days 25.0 25.0 25.0 11.0 21.0 (3620) (3620) (3620) (1600) (3050) Heat of Hydration, max., kJ/kg (cal/g): 7 days 290 290 290 ... 250 (70) (70) (70) ... (60) 28 days 330 330 330 ... 290 (80) (80) (80) ... (70) IP IP(LH), IS (<70) IL(LH), IL IS (< 70) (MS), IS (< 70) (HS), IT(P≥S)(LH) IT(P≥S) IT(P<S<70)(MS) IT(P<S<70)(HS) IS(≥70), IT(L<S<70)(L IT(P>L) IP(MS), IP (HS), IT(S≥70) H), IT(L≥S) IT(P≥S)(MS) IT(P≥S)(HS) IT(P>L)(LH) IT(L≥P) IT(L≥S)(LH) IT(L<S<70) IT(L≥P)(LH) IT(P<S<70) Water req. ... ... ... ... 64 max % Drying shrinkage, ... ... ... ... 0.15 max, % Mortar expansion, max, %: 14 days 0.020 0.020 0.020 0.020 0.020 8 weeks 0.060 0.060 0.060 0.060 0.060 Sulfate resistance, expansion, max, %: at 180 d 0.10 0.05 at 1 year 0.10 Chemical Requirements for Blended Cements IS(< 70), I P, IL IS(≥70), Cement Type IT(P<S<70), IT(P≥S), IT(L≥S), IT(S≥70) IT(L<S<70) IT(P>L) IT(L≥P) MgO, max, % . 6.0 . SO3, max, % 3.0 4.0 4.0 3.0 S2-, max, % 2.0 2.0 ... Insol. res. max, %C 1.0 1.0 ... LOI, max, % 3.0D 4.0D 5.0D 10.0 C Insol res max does not apply to ternary blended cements. D For ternary blended cements with limestone LOI max = 10%. Requirements for Limestone for Use in Blended Cements Test Method Limit CaCO3 content C114/T105 Min. 70% Methylene blue index See Annex A2 Max. 1.2 g/100g Total organic carbon See Annex A3 Max. 0.5% Limestone Testing Summary Portland-limestone blended cements 5% to 15% limestone History of use: Europe, Canada, US Mechanisms An option to make greener concrete Additional information [email protected] Portland Limestone Blended Cement in ASTMThank C595 you! and AASHTO M240 Presented to ASTM C01.10 December 2010 North American PLC Pavements Field Applications in Canada, Utah and Colorado Todd Laker, Holcim (US) Inc. Brooke Smartz, Holcim (US) Inc. 1 Portland-Limestone Cement Paving Projects . +125 miles of concrete paving in Colorado and Utah Performance and Environmental Benefit 2 CDOT and UDOT Specifications . Allow portland-limestone cements that meet ASTM C1157 performance specification for GU (General Use), MS (Moderate Sulfate Resistance) and HS (High Sulfate Resistance) . Supplementary cementitious materials required for applications that require resistance for sulfate attack and/or alkali silica reactivity for both ASTM C150 and ASTM C1157 cements 3 Verifying Portland Limestone Cement Durability . Holcim ASTM C595 (Type IL) or ASTM C1157 cements are tested for durability performance. Tests generally include: Fresh & Hardened concrete properties - Requirements are met through concrete mix design – ASTM Sulfate Resistance - ASTM C1012 Alkali-Silica Reactivity - ASTM C1260/1567 Freeze Thaw & Deicer Scaling Resistance - ASTM C666 & C672 Shrinkage – ASTM C157 Chloride Ion Penetration – ASTM C1202 4 How do Portland-Limestone Cements compare? ASTM Designation PLC vs C150 PLC vs C150 PLC vs C150 PLC vs C150 PLC vs C150 Strength 28D (C39) Equal Better Better Better Equal Sulfate (C1012) Equal Equal Equal Equal Equal ASR (C1260/C1567) Better Equal Equal Equal Equal Freeze-Thaw (C666) Equal Equal Equal Equal Equal Deicer Scaling Equal Equal Equal Equal Equal (C672) Shrinkage (C157) Equal Equal Equal Equal Equal Permeability Slightly Better Equal Equal Equal Equal (C1202) 5 How do Portland-Limestone cements perform in the field? . Equal or improved to C150 cements Strength Set time Water demand Compatibility with fly ash Compatibility with admixtures . Improved finishability . Lower environmental impact 6 Devil’s Slide, Utah Cements . Type V clinker C3A <5% . ASTM C150 Type II/V High sulfate resistance - C3A <5% <5% limestone per ASTM C150 Naeq <0.60% .